Escapement mechanism.



O. EGGEBRECHT.

ESGAPEMENT MECHANISM.

7 APPLICATION rum) Mum. 1910.

Patented. Sept 6, 1910.

n4: NORRIS PETERS co UNITED STATES rATENT onnion.

OTTO EGGEBRECHT, OF MOMENCE, ILLINOIS, ASSIGNOR T0 TI-IE EMERSONTYPEWR-ITER COMPANY, OF CHICAGO, ILLINOIS, A CORPORATION OF ILLINOIS.

ESCAIPEMENT MECHANISM.

Specification of Letters Patent.

Patented Sept. 6, 1910.

Application filed March 8, 1910. Serial No. 548,622.

T 0 all whom it may concern:

Be it known that I, Orro Eeennnncnr, a citizen of the United States,residing at Momence, in the county of Kanka-kee and State of Illinois,have invented certain new and useful Improvements in EscapementMechanism, of which the following is a specification.

The typewriter of the present invention employs a universal bar adaptedto be actuated by the depression of any key, the movement of which barserves, through suitable connections, to actuate the ribbon lift andalso the escapement dogs.

The object of the present invention is to so construct the operatingdevices, which are actuated by the universal bar, that the ribbon willbe completely lifted prior to the actuating of the carriage escapement,which allows the key lever to act freely at the beginning of the strokeand throws the pressure of the escapement action onto the key lever atthe end of the strbke at a time when the type bar has acquiredsufficient momentum to accommodate the additional load thrown onto thetype bar. The result of this arrangement is to ease the stroke of thekeys very materially, and at the same time permit the escapement to beactuated by a very slight movement at the end of the key lever stroke.

Another object of the invention is to actuate the escapement mechanismdirectly from the movements of a member carried by the draw bar, and toso arrange the connection between this member and the draw bar that themember will be moved at the end of the stroke of the draw bar.

Further objects will appear from a detailed description of theinvention, which consists in the features of construction andcombination of parts hereinafter described and claimed.

In the drawings, Figure l is'a longitudinal sectional elevation fromfront to rear of the typewriter, showing those portions of the mechanismwhich relate to the present invention, with a key lever in elevatedposition; Fig. 2, a similar view, showing the key lever depressed; andFig. 3, a perspective detail of the ribbon lift.

The frame of the typewriter comprises side walls 7, a fiat rectangulartop wall 8, and front and rear walls 9 and 10, respectively.

The side walls are carried forward in the form of extensions 11, whichare connected at their front ends by a front rail 12, which arrangementfurnishes a space for the location of several banks of keys, only onekey being shown in the present drawings. The front wall 9 isprovided, inits lower edge, with a plurality of slots 13, one for each of aplurality of key levers let, each of which, at its forward end 15, isupturned to receive a button 16 of the usual character. The key leversare all hinged to a trans versely extending key lever rod 17, the endsof which are supported within the side walls of the frame. Each of thekey levers is provided, at its inner end, with a vertically extendingarm 18, from which extends a link 19, which serves to actuate avertically pivoted type bar 20. When any key is depressed, its type barwill be swung to the center of the machine to a point marked X, whichindicates the striking point on the writing line, but, in view of thefact that the present invention is not concerned with the constructionof the type bar or its mode of operation, it is not deemed necessary torefer to these features in detail.

Each of the key levers is provided, immediately in front of the arm 18,with an upwardly extending prong 21, which prong engages a universal bar22, which is hing-ed at its upper edge to a transversely extending rod23, the arrangement being one whereby the free end of the universal barwill be swung forward with each depression of the key lever, as clearlyindicated in Fig. 2. The universal bar has secured thereto a dependingarm 24, which extends below the line of the key levers, and is pivotedat its lower end to a draw bar The draw bar comprises a. straight frontsection 26, and a straight rear section 27, parallel and offset withrespect to one another, and connected by means of a diagonally extendingintermediate section 28 carrying a laterally projecting pin 29. The pin2.) engages a slot 30 in the lower end of a dog arm 31, which is pivotedto a feed shaft 32, on which is rigidly mounted a ratchet wheel 33. Thedog arm, at its upper end, carries a dog 34, which engages the teeth ofthe ratchet wheel and is adapted to impart intermittent rotation theretoin the direction of the arrow.

The feed shaft serves, by means of beveled gearing 35, to impartrotation to a vertical feed shaft 36, which carries a ribbon feed wheel37 adapted to impart horizontal movement to a ribbon 38, which ribbon isentered through guide prongs 39 and 39 on the upper ends of the verticalarms 40 and 40 of a ribbon holder 41,as shown in Fig. 3. The ribbonholder is pivoted at the forward end of a lift plate 42, the rear end ofwhich is provided with upturned ears 43, pivoted between the ends of abracket 44 secured to the rear wall of the frame. The lift plate isprovided, in its center, with a slot 45, which is bridged by a cross rod46, the ends of which are entered into ears 47 struck up from the sideedges of the lift plate.

The rear section of the draw bar terminates in a depending head 48,provided in its front edge with a recess 49, the lower edge 50 of whichis sloped or beveled, to provide a cam member 51 which engages the crossrod 46, with the result that, when the draw bar is drawn forward, thecam extension will ride under the cross rod 46 and raise the lift plate,thereby lifting the ribbon holder. The depending head terminates, at itsrear end, in a prong 52, which is pivoted to a link 53, the lower end ofwhich is mounted on a pivot rod 54, which also serves to pivot the rearend of the lift plate. In order to aid in returning the draw bar to itsnormal retracted position, a coil spring 55 is interposed between thedepending head 48 and the lower end of the link 53, with the result thatas the head is drawn forward the spring will be extended.

The rear section of the draw bar serves as a mounting for an escapementactuating member 56, which, as shown, is in the form of an elongatedplate provided with slots 57 which receive headed pins 58. The plate, asshown, is formed with an upwardly extending portion 59, which is formedwith a slot 60 adapted to receive a stud or pin 61 projecting from aswinging arm 62, which carries the escapement mechanism 63. The arm 62extends downwardly, and has its lower portion 64 normally contacting astop 55, which projects out from the rear wall of the frame; andattached to the rear of the upwardly extending portion 59 is a spring66, secured to an adjusting screw 67 entered into the rear wall of theframe, the spring 66 serving to return the member 56 to normal positionupon the return stroke of the key levers.

It is not deemed necessary to show the rack and platen of the machine,since the present invention is not concerned with the details of thismechanism.

In operation, the depression of any key will swing forward the universalbar simultaneously with the swing of the type bar, and this forwardmovement of the universal bar will cause a forward movement of the drawbar 25, which will actuate the dog 34 and impart a feeding movement tothe ribbon. The same movement of the draw bar will cause the cam surface50 of the cam extension 51 to ride under the cross rod 46 of the liftplate, so that the ribbon will be lifted at the beginning of theprinting stroke and will be fully raised prior to the final completionof the stroke and prior to the escapement. At the end. of the stroke,the releasing device 56 will be drawn forward, putting the draw barunder increased tension at the very completion of the stroke and at atime when the type bar has acquired its greatest momentum toward thecompletion of its swing, so that the additional pressure necessary to beexerted on the keys, in order to effect the escapement, will hardly benoticed by the operator, as would be the case if the actuation of theescapement devices were effected earlier in the stroke.

As shown in Fig. 1, when the escapement mechanism is in normal position,the mem her for actuating the escapement mechanism will be held inposition, so that the headed pin will lie midway of the slot 57 hencethe initial movement of the draw bar to operate the ribbon feed andribbon lifting mechanism will impart no movement to the escapementactuating member, but, after the draw bar has traveled a sufiicientdistance to bring the pins into engagement with the ends of the slot 57,movement will'be imparted to the escapement actuating memher, and thismovement of the member will act directly to actuate the escapementmechanism 63, and, as will be seen, this movement will occur toward theend of the stroke of the key lever and the end of the movement of thedraw bar, and as, at this time, the type bar will have acquired itsgreatest momentum, the additional pressure on the key lever necessary tooperate the escapement mechanism will not be noticed by the operator. 7,

It will be seen from the foregoing description that the arrangement isone which relieves the keys in large measure from the pressure necessaryto actuate the escapement dogs, so that the action of the machine willbe correspondingly lightened.

I claim:

1.- In ribbon lift and escapement mechanism, the-combination of keylevers and keys, a universal bar adapted to be actuated by thedepression of a key, escapement devices the key lever, and a stop memberfor maintaining the escapement mechanism in normal position,substantially as described.

2. In ribbon lift andescapement mechanism, the combination of key leversand keys, a universal bar adapted to be actuated by the depression of akey, a pivoted escape ment dog, an arm depending from the dog, a drawbar connected with and rearwardly extending from the universal bar, amember carried by the draw bar for actuating the ribbon liftat thebeginning of a printing stroke, and an actuating member for theescapement mechanism, slidably mounted on the draw bar and in constantcontact with the depending arm, said escapement actuating member beingoperated to move the escapement dog toward the end of the movement ofthe draw bar, substantially as described.

3. In ribbon lift and escapement mechanism, the combination of keylevers and keys, a universal bar adapted to be actuated by thedepression of a key, a pivoted escapement dog, an arm depending from thedog, a draw bar connected with and extending rearwardly from theuniversal bar, a member carried by the draw bar for actuating the ribbonlift at the beginning of a printing stroke, an actuating member for theescapement mechanism, slidably mounted on the draw bar and in constantcontact with the depending arm, said escapement actuating member beingoperated to move the escapement dog toward the end of the movement ofthe draw bar, and a stop member against which a portion of theescapement mechanism normally rests, substantially as described.

4. In ribbon lift and escapement mechanism, the combination of keylevers and keys, a universal bar adapted to be actuated by thedepression of a key, a draw bar connected with the universal bar, andprovided with a depending head furnishing a cam member, a ribbon liftplate adapted to be elevated by a movement of the cam, an escapementdog, an actuating member for the escapement dog, carried by and slidablymounted on the draw bar, said escapement actuating member being inconstant engagement with said draw bar and imparting movement directlyto said escapement dog, said draw bar imparting motion to saidescapement actuating member toward the end of the printing stroke,substantially as de scribed.

5. In ribbon lift and escapement mechanism, the combination of keylevers and keys, a universal bar adapted to be actuated by thedepression of a key, escapement devices and ribbon lift devices, a drawbar, actuated by the universal bar and acting directly upon the ribbonlift devices, a non-resilient member for actuating the escapement de-Vices, and held in constant operative engagement therewith, and a lostmotion connection between the escapement actuating member and the drawbar, substantially as described.

6. In ribbon lift and escapement mechanism, the combination of keylevers and keys, a universal bar adapted to be actuated by thedepression of a key, escapement devices and ribbon lift device, a drawbar, actuated by the universal bar and acting directly upon the ribbonlift devices, a non-resilient member for actuating the escapementdevices, and held in constant operative engagement therewith, a lostmotion connection between the escapement actuating member and the drawbar, and means for returning the escapement actuating member to normalposition, substantially as described.

7. In ribbon lift and escapement mechanism, the combination of keylevers and keys, a universal bar adapted to be actuated by thedepression of av key, escapement devices and ribbon lift devices, a drawbar, actuated by the universal bar and acting directly upon the ribbonlift devices, a non-resilient member for actuating the escapementdevices, and held in constant operative engagement therewith, a lostmotion connection between the escapement actuating member and the drawbar, and a stop member against which a portion of the escapementmechanism normally rests, substantially as described.

8. In mechanism of the class described, the combination of key leversand keys, a universal bar adapted to be actuated by the depression of akey, escapement devices, a member for actuating the escapement de vices,having a slot therein, a draw bar connected with the universal bar, apin carried by the draw bar and lying within the slot in the escapementactuating device, the pin contacting the end of the slot and moving theescapement actuating mechanism toward the end of the movement of thedraw bar, substantially as described.

9. In mechanism of the class described, the combination of key leversand keys, a universal bar adapted to be actuated by the depression of akey, escapement devices, a member for actuating the escapement devices,having a slot therein, a draw bar connected with the universal bar, apin carried by the draw bar and lying within the slot in the escapementactuating device, the pin contacting the end of the slot and moving theescapement actuating mechanism toward the end of the movement of thedraw bar, and means for returning the escapement operating member tonormal position, substantially as described.

10. In mechanism of the class described, the combination of key leversand keys, a universal bar adapted to be actuated by the depression of akey, escapement devices, a

member for actuating the escapement debar and a stop member againstwhich a porvices, having a slot therein, a draw bar contion of theescapement mechanism normally 10 Irgectecl with 'tlge universal bar, apin carriled i rests, substantially as described.

y the draw at and lying Within the s 0t in the escapement actuatingmechanism, the O EGGEBRECHT'Y pin contacting the end of the slot andmov- I Witnesses: 1 ing the escapement actuating mechanism to- WM. P.BOND,

ward the end of the movement of the draw EPHRAIM BANNINGT

